The present invention relates to yarn processing machines in general, and more particularly to an arrangement for and a method of supervising the operation or performance of such yarn processing machines.
There are already known various constructions of yarn processing machines, among them such which include a plurality of individually operatable yarn processing stations. Examples of such machines are rotor spinning machines, air-jet of "false-twist" yarn spinning machines, automatic winding machines, and false twist texturizing machines.
The expression "independently operatable" as used in the present disclosure is to be understood as indicating the situation where the processing of yarn at one of the plurality of stations can be terminated or interrupted and later commenced again without affecting in any way the processing of yarn at any other station of the same plurality. However, this expression does not exclude, and actually embraces, the possibility of providing, for example, common drive systems for the yarn processing stations of the plurality, or common services for such stations, such as pneumatic suction systems.
There is a current accelerating trend toward the incorporation of at least limited data processing functions in yarn processing machines of the type mentioned above. Such data processing systems are being offered, on the one hand, by the manufacturers of such yarn processing machines, and on the other hand, by independent suppliers of such equipment, for example the firm Zellweger A.G. of Uster, Switzerland. Systems of this type have been in development over a considerable period of time, as may be ascertained from a collection of articles that have been published in the April 1973 edition of Melliand Textil Berichte.
A common feature of these systems is that the information concerning the current operating condition of each individual yarn processing station is collected and stored in a "condition register" of one kind or another which is incorporated in or otherwise forms a part of a central monitoring unit. The information stored in this condition register is updated at a rate that is dependent upon a predetermined sampling cycle frequency, each processing station being interrogated to determine its current operating condition during each sampling or scanning cycle. A broad outline of systems of this type will be described later in this description. However, since the details of such a system are not crucial for understanding the present invention, and since adequate details are readily ascertainable from the relevant literature which is known or easily accessible to those active in the yarn processing field, such details of the sampling and data transmission systems will be omitted from the present specification.
There is, furthermore, a more recent trend toward providing the machines of the type here under consideration with yarn quality monitoring systems. Such systems are being offered, for instance, by the firm Zellweger A.G. mentioned above, by the firm Otto Stuber KG Textilmachinen-Apparate of Bussingen, Federal Republic Germany, and by the firm Siegfried Peyer of Baech, Schwyz, Switzerland. These systems monitor the yarn leaving the main processing unit of each individual processing station and, in response to the detection of a "defect" at a particular station, they (a) interrupt the operation of that station, and (b) record the occurence of the defect in a "quality defect register" which is shared by all of the monitored stations.
Within the design limits of such a system, the yarn characteristics which may constitute a "defect" can be determined or selected by the machine user, being constituted by a deviation, or a combination of deviations, from some predetermined standard or standards.
A broad outline of a quality monitoring system of this type will be described later in this description. However, once more, since the details of the systems of this kind are not essential to the present invention or its understanding, and since information concerning such details is available from respective patents assigned to the companies offering such systems (and to others), no details of such yarn quality monitoring systems will be, nor need they be, discussed in the present specification. The invention will be readily understood without such details.
As advantageous and useful as these systems may be, however, experience with them has shown that they suffer of many drawbacks, particularly their incapability of gathering and evaluating pertinent data and associating such data with the particular stations at which the problems arise either from time to time, or with a high frequency, so that it is difficult if not impossible when using such known systems to take immediate remedial action at the affected station.